WASHINGTON -- Mine rescue workers yesterday told federal mine safety officials that they couldn't understand how U.S. officials have managed to speak to astronauts on the moon, yet still haven't figured out how to help mine workers communicate underground after an accident.

But they may not have gotten much comfort from a day of presentations about new technologies, which ranged from a self-repairing, wireless mesh network that might give miners the ability to text-message each other from special watches to a proposal for a miner tracking system based on submarine technology. Many of these products are untested in mines and a long way from approval.

At the end of a long day, Jim Ponceroff, who heads a mine rescue team in Blacksville, W.Va., pleaded with mine safety officials to pursue practical solutions and expressed concern that the current political pressure could lead to complicated but ineffective new systems underground.

"I hear guys here all day telling me how nice these systems are, but apparently they haven't been underground in a coal mine after an explosion," Mr. Ponceroff said. "Metal beams are twisted and bent double, lunch buckets are smashed flat. ... A piece of plastic ain't going to make it.

"We've got public outcry now because men lost their lives, so we need to do something," he said. "But don't be hasty and do something that's not going to be right."

Mr. Ponceroff spoke during hearing in Washington at which the Mine Safety and Health Administration, or MSHA, had asked technology firms to present new devices for underground communication and tracking of miners.

Companies from the United States, Australia and Canada showed items such as caps with built-in personal emergency and radio devices -- some of which are already approved -- and a hands-free micro-thermal camera mounted on a helmet.

Mine rescue teams or miners could use the camera, which essentially illuminates objects with heat sensors, to help them find their way through the darkness after an explosion.

Several technology firms, including QuickStart Wireless of Pittsburgh, made presentations about the potential of creating underground voice and e-mail communication systems carried by wireless networks -- a new area that the MSHA is just beginning to explore.

But since the recent Sago and Alma mine accidents in West Virginia, agency officials have mainly been investigating the effectiveness of personal emergency devices, or PEDs, that are being tested in some U.S. mines, as well as miner tracking systems used in Australia. Some lawmakers are considering mandating those systems in U.S. mines, and the MSHA is preparing its final report on the technologies.

Yesterday, the federal officials heard testimony on PEDs from a top official at Peabody Energy Corp., which has been testing the devices at Peabody Air Quality Mine in Indiana and at the Twentymile Mine in Colorado.

Dave Beerbower, Peabody's vice president of safety, told officials that the company has had mixed results. He said U.S. companies will face difficulties placing the PED system's antenna above ground -- which can help the system reach more miners in remote areas -- when the mining firm does not own the land above ground.

Mr. Beerbower said Peabody was also concerned about whether proposed legislation would inflict penalties if PED devices should hit dead zones inside mines, as they have during testing.

"I think there's a lot more research that needs to be done," he said of PED devices. "They are reliable in most cases. ... They can deliver one-way text messages to most miners in almost every underground coal mine. That, however, differs greatly from what has been proposed as legislation that says [the device] must be able to communicate with all miners in every location underground."

But miner advocates and PED technology proponents said it is one of the devices with the most potential to be put in place quickly in U.S. mines, in part because some of them have already been approved.

"If I have a system that works half the time or that applies to half or 75 percent of [a] mine on a routine basis, ... that's 50 percent better than what I have now," said Tim Baker, who handles safety issues for the United Mine Workers of America.

Several officials from small companies yesterday also complained that the slow pace of the MSHA approval process has stymied new technology. Some said it is one of the reasons that so few communication methods are ready for use in U.S. mines.

Federal officials acknowledged, for example, that there are no MSHA-approved hand-held, two-way communication devices on the market at the present time, because the one company whose radios were approved stopped making them, and the agency is still evaluating the safety of other two-way radios.